Studies conducted by Underwriters Laboratories (UL), National Institute of Standards and Technology (NIST), and The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) Fire Research Laboratory have concluded that ventilation flow paths within a structure fire are directly attributed to the spread of fire, and the loss of lives and property. The above studies proved that controlling the amount of opening of the door (i.e. door control) used by firefighters is the valve for limiting flow path. Flow path is the volume between an inlet and an outlet that allows the movement of heat and smoke from higher pressure within the fire area toward the lower pressure areas accessible via door and window openings. Firefighting operations conducted in the flow path, between the fire and where the fire wants to go, will place civilians and firefighters at significant risk due to the increase flow of fire, heat and smoke toward their position. Fire, heat and smoke also can cause structural members to fail or windows to shatter causing rapid changes in flow path within a structure. These rapid changes may necessitate the emergent evacuation of firefighting personnel.
Door control has been identified as the most important component in restricting the flow of air into a building that is on fire. Lack of flow path control, by either intentional or unintentional ventilation of a building on fire has been proven to accelerate progression of the fire. This resulting rapid fire progression has resulted in civilian and firefighter injuries and deaths. Most fire departments do not have enough manpower on a scene to allow dedication of a member to stay at the entry door keeping it closed as much as possible while crews operate inside the building with a fire hose line.
The conventional means for controlling exterior and interior doors is a wooden or plastic triangular wedge. These tools have been used in the fire service for decades, but offer little to no assurance that they will fix a door in place while resisting force from all directions that occur during firefighting operations, such as advancing a fire hose line into and throughout the structure. Most importantly, the conventional wedge in no way offers a means for efficient and rapid removal thereof during emergency egress by firefighters.